Lubricant



Patented Apr. 1, 1941 UNITED STATES PATENT OFFICE No Drawing. Application September 22, 1939, Serial No. 296,096

11 Claims.

(Granted under the act or March 3, 1883, as amended April 30, 1928; 370 0. G. 757-) This application is made under the act of March 3, 1883, as amended by the act of April 30, 1928, and the invention herein described, if patented, may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment to me of any royalty thereon.

This application is a continuation in part of my application for patent Serial No. 189,961, filed February 11, 1938.

This invention relates to new compounds, useful as lubricant bases, prepared by'reacting sulfurized unsaturated monocarboxylic acids with compounds of the class consisting of alkali-salts, alkaline earth salts, and heavy metal salts.

The object of this invention is the provision of compounds suitable in compounding lubricants and reases for use under extreme pressure.

More specifically, the object is to provide a amount of sulphur that may be chemically added to the unsaturated acid is dependent upon the number of .double bonds in the acid molecule.

For each'double bond one atom of sulphur maybe added to saturate that bond. Acids containing more than one double bond form a series of sulphurized acids, which are designated as the mono-, the di-, the tri-, etc., depending upon the number, of double bonds saturated with sulphur. The following examples are given to ill5 lustrate the formation of these sulphurized acids.

1. Oleic acid series Oleic acid contains only one double bond and hence can form only one sulphurized a'cld Oleic acid type of non-corrosive. sulphur-containing metal 1 soaps with which desired lubricants can be compounded by admixture with suitable amounts of appropriate mineral lubricating oils.

Another object of this invention is to provide a method of manufacturing the improved bases.

for compounding lubricants.

It is well known that sulphur and sulphur compounds are desirable extreme-pressure agents in lubrication, increasing the capacity of an oil film to hold surfaces apart. Also, results of engine tests with lubricants containing metallic soaps, such as tin oleate, show them to be inhibitors of oxidation.

Another object of this invention is to produce compounds possessing these two features, en-,

hancing the oiliness of a lubricant and retarding oxidation, without appreciably increasing its Sulphur 9-10 monosulphur-octadecanoic 2. Linoleic acid series Linoleic acid contains two double bonds in its molecule and combines with one or two atoms of surphur forming the monoand diseries ofv acids as shown by the following equations:

S Octadecadien-Q, l2-1nonosulphur-oic acid v I Octadecadien-Q, lz-disulphur-oic acid 3. Linolem'c acid series Linolenic acid contains three double bonds in its molecule and combines with one, two, and

2 2,237,09e v three atoms of sulphur, producing the 'corre- EXAMPLE l.Sodium salts of sulphurized linoeic sponding sulphurized acids. acid (a) Octadecadien-9, lz-monosulphur-oic acid. (0.) Sodium saltof octadecadien-Q, 12-monoan hour or longer after the exothermic reaction 50 Linolenic acid Sulphur ctadecadien-9, l2-monosulphur -oic acid (b) Octadecadien-S), l2-disulphur-oic acid.

(0) Octatrian-9, 12, l5-trisulphur-oic acid.

The sulphurized monocarboxylic acids, whether sulphur-01c acid. mono-, di-, tri-, etc., react with alkalies forming I I H H the corresponding salts, which can be purified by repeated salting out from solution in a similar CH3(CH C 7lJ'CHCH=CH(CHM:0H+NaOH= manner as used in the manufacture of soaps. A solution of these new alkali salts reacts with the 400mm allllglline earth and heavy metal salts, forming new I H. Y a ine earth and heavy metal compounds. x

The preferred method of manufacturing these 40 CH'wHMCW'CHC{Lemomm02m compounds is to heat a free unsaturated mono- 3333? carboxylic acid with the appropriate amount of v i sulphur at a. temperature ranging between 160- (b) Sodium salt of octadecadien-9, 12-disulphur- 200 0., using iodine as a catalyst, until the suloic acid. phurized acids have been formed as shown by an H exothermic reaction. An inert gas, such as carl g bon dioxide, is kept over the acid while heating 7 and during the cooling process to prevent oxida- S tion., Heating is preferably continued for half H H H H4001 stops to insurecomplete chemical reaction, and f'j w saturation of the double bond or bonds with sul- Phur; Glycerides 01' the unsaturated monocar- I 365395118 1 boxylic acids, or animal and vegetable oils con- EXAMPLE 2 Th s dium mono-, di-, and tritaining t m. ay be e p y d i pla of th compounds of .sulphurized linolenic acid may be acids. The sulphurized acids are neutralized with prepared as in the above example, using the a solution of sodium hydroxide, and purified by formulas for the different acids previously depeated salting o t ro so o f a glycellde scribed, by reacting one mole of the sulphurized or 011 s been flfuri ed. it is saponified b diacid with one mole of sodium hydroxide.-

gesting with sodium hydroxide solution, and then purified in the same way as outlined above. To EXAMPLE 3- Lead salts of mmbsulphur' form the alkali earth and heavy metal salts the .octadecanoic following procedure is used:

To a hot solution of the alkali salt of the sulphurized acid is added a hot solution of an alkallne earth or heavy metal salt, causing the .premole of s1ub le1ead salt cipitation of the corresponding sulphur com- 1 III III pound. The compounds are well washed and CH CH C C CH COON PbNO: dried. Most 01. the metallic salts of the sula a phurized acids are amorphous compounds which f 33122 are soluble in mineral'oil on heating. They are chloroform, benzene and other hydrocarbons. Typical examples of the formation oisome of Partially soluble in organic solvents such as H CH:(CHn)1l-4J (011101002 Pb these new compounds are given below. 833-86 This compound is prepared by reacting two moles oi the-corresponding sodium salt and one EXAMPLE 4.Copper salts of octadecadien-9, iz-monosulphur-oic acid These two compounds are prepared by reacting two moles of the corresponding sodium salt with one mole of a soluble copper salt, producing the a respectively These two compounds are formed when two v moles of the corresponding sodium salt are re- The copper compounds are green waxllke substances soluble in carbon tetrachloride, chloroform, and mineral oils when heated.

EXAMPLE 5.-Tin salts of octadecadien-S), 12- monosuZphur-oic acid and octadecadian-9, 12- disulphur-oic acid 7 The tin compounds are yellowish white, puttylike substances soluble in mineral oils when heated.

YEXALZIPLE 6.C'alcium salt of 9-10 monosulphuroctadecanoic acid When two moles of the sodium salt of 9-10 monosulphur-octadecanoic acid are reacted with one mole of a soluble calcium salt, the calcium salt of 9-10 monosulphur-octadecanoic acid is formed. This compound is of a yellowish white in color, amorphous in nature and forms an emulsion with mineral oils when heated. It ha the general formula (C1aHasO2S)2Ca.

Exmrr.u 'L-Magnesium salts of octadecddien-Q,

IZ-mOnosuZphuT-Oic and octadecadian-S', 12-

disuZphur-oic acid acted with one mole of a soluble magnesium salt. The formulas of the two compounds are (CmHsrOzS) Mg and (CraHnOzSz) :Mg respectively. The compounds are amorphous and of a. yellowish white in color. They form emulsions with mineral oils.

Having thus described my invention, I claim:

1. A lubricant containing in solution an alkaline earth salt of a sulphurized monocarboxylic acid to inhibit oxidation.

2. A lubricant containing in solution a heavy metal ,salt of a sulphurized mono'carboxylic acid to inhibit oxidation.

3. A lubricant containing in solution a lead salt of 9-10-monosulphur-octadecanoic acid as an oxidation inhibitor.

4. A lubricant containing in solution a sodium salt of octadecadien-Q, lz-monosulphur-oic acid as an oxidation inhibitor.

5. A lubricant containing in solution a sodium salt of octadecadian-Si, IZ-disulphur-oic acid to inhibit oxidation.

6. A lubricant containing in solution a sodium salt of octatrian-9, l2, l5-trisulphur-oic acid to inhibit oxidation.

7. Alubricant containing in solution a copper salt of octadecadien-9, 12-monosulphur-oic acid I to inhibit oxidation.

8. A lubricant containing in solution a copper salt of octadecadian-9, lz-disulphur-oic acid to inhibit oxidation.

9. A lubricant containing in solution acalcium salt of 9, 10-monosu1phur-octadecanoic acid to inhibit oxidation.

10. A lubricant containing in solution a magnesium saltot octadecadien-9, lz-mon'osulphuroic acid to inhibit oxidation.

11. A lubricant containing in solution a magnesium salt of octadecadian-9, lz-disulphur-oic acid toinhibit oxidation.

FREDERICK E. DEARBORN. 

